Method and device for measuring signals

ABSTRACT

Sinusoidal drive is used, and a coefficient table for a plurality of predetermined phases is established, wherein each predetermined phase is designated with a coefficient. A sinusoidal wave is measured at the plurality of predetermined phases of each half cycle to produce measured signals, and each of the measured signals is multiplied with the coefficient corresponding to the phase at which the signal is measured to produce a weighted measured signal. Then, the weighted measured signals are summed to produce a complete measured signal.

CROSS REFERENCE TO RELATED PATENT APPLICATION

This patent application claims the domestic priority of the U.S.provisional application 61/617,196 filed on Mar. 29, 2012, and thebenefit of Taiwan Application Serial No. 101150798, filed on Dec. 28,2012, which is herein incorporated by reference for all intents andpurposes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method and device for measuringsignals, and more particularly, to a method and device for using signalorthogonality as the basis for measuring signals.

2. Description of the Prior Art

A conventional mutual capacitive sensor includes an insulating surfacelayer, a first conductive layer, a dielectric layer, a second conductivelayer. The first conductive layer and the second conductive layer have aplurality of first conductive strips and a plurality of secondconductive strips, respectively. Each of these conductive strips can bemade up by a plurality of conductive pads and connecting lines connectedto the conductive pads in series.

In the process of mutual capacitive detection, one of the firstconductive layer and the second conductive layer is driven, while theother of the first conductive layer and the second conductive layer isdetected. For example, a driving signal is sequentially provided to eachfirst conductive strip, and corresponding to each first conductive stripprovided with the driving signal, signals from all of the secondconductive strips are detected, which represent capacitive couplingsignals at the intersections between the first conductive strip providedwith the driving signal and all the second conductive strips. As aresult, capacitive coupling signals at the intersections between all thefirst and second conductive strips are obtained to form an image ofcapacitive values.

Accordingly, the image of capacitive values at the time when there is noexternal touches is obtained as a reference. By comparing the differencebetween the reference image and the image of capacitive values laterdetected, the touch or approach of an external conductive object can bedetermined, and furthermore, the position touched or approached by theexternal conductive object can be determined. However, a lot of noiseinterferences are present in the surrounding environment, especially lowfrequency noise interferences, which might lead to misjudgments orerrors in determined touch locations.

From the above it is clear that prior art still has shortcomings. Inorder to solve these problems, efforts have long been made in vain,while ordinary products and methods offering no appropriate structuresand methods. Thus, there is a need in the industry for a novel techniquethat solves these problems.

SUMMARY OF THE INVENTION

When signal orthogonality is used as the basis for signal processing,square-wave drive will produce many odd harmonics. When a narrowbandinterference occurs near an odd harmonics, this interference cannot beeliminated. One objective of the present invention is to use sinusoidaldrive, and establish a coefficient table for a plurality ofpredetermined phases, wherein each predetermined phase is designatedwith a coefficient. A sinusoidal wave is measured at the plurality ofpredetermined phases of each half cycle to produce measured signals, andeach of the measured signals is multiplied with the coefficientcorresponding to the phase at which the signal is measured to produce aweighted measured signal. Then, the weighted measured signals are summedto produce a complete measured signal, thereby suppressing theinterferences of higher-order harmonics.

The above and other objectives of the present invention can be achievedby the following technical scheme. A method for measuring signals inaccordance with the present invention may include: receiving asinusoidal wave; measuring signals from the sinusoidal wave at aplurality of predetermined phases of at least a cycle of the sinusoidalwave; producing a weighted measured signal of the at least one cyclebased on a product generated by multiplying each measured signal of theat least one cycle with the sine value of the predetermined phase atwhich the particular signal was measured; and summing all of theweighted measured signals of the at least one cycle to produce acomplete measured signal.

The above and other objectives of the present invention can also beachieved by the following technical scheme. A device for measuringsignals in accordance with the present invention may include: an analogmeasuring circuit for receiving a sinusoidal wave and measuring analogsignals from the sinusoidal wave at a plurality of predetermined phasesof at least a cycle of the sinusoidal wave; an analog-to-digitalconverter for converting each analog measured signal into a digitalmeasured signal; and a processor for producing a digital weightedmeasured signal of the at least one cycle based on a product generatedby multiplying each digital measured signal of the at least one cyclewith the sine value of the predetermined phase at which the particularsignal was measured, and summing all of the digital weighted measuredsignals of the at least one cycle to produce a complete measured signal.

The above and other objectives of the present invention can also beachieved by the following technical scheme. A device for measuringsignals in accordance with the present invention may include: an analogmeasuring circuit for receiving a sinusoidal wave and measuring analogsignals from the sinusoidal wave at a plurality of predetermined phasesof at least a cycle of the sinusoidal wave; an amplifying circuit foramplifying each analog measured signal with a multiple of the sine valueof the predetermined phase at which the particular signal was measuredto produce an analog weighted measured signal; an analog-to-digitalconverter for converting each analog weighted measured signal into adigital weighted measured signal; and a processor for summing all of thedigital weighted measured signals of the at least one cycle to produce acomplete measured signal.

The above and other objectives of the present invention can also beachieved by the following technical scheme. A device for measuringsignals in accordance with the present invention may include: an analogmeasuring circuit for receiving a sinusoidal wave and measuring analogsignals from the sinusoidal wave at a plurality of predetermined phasesof at least a cycle of the sinusoidal wave; an amplifying circuit foramplifying each analog measured signal with a multiple of the sine valueof the predetermined phase at which the particular signal was measuredto produce an analog weighted measured signal; an integrator circuit forperforming integration on all of the analog measured signals of the atleast one cycle to produce an analog complete measured signal; and ananalog-to-digital converter for converting each analog complete measuredsignal into a digital complete measured signal.

With the above technical scheme, the present invention includes at leastthe following advantages and beneficial effects:

1. The interferences of higher-order harmonics are suppressed;

2. The processing requires no complicated circuits, but rather simpledigital logical circuits; and

3. Integer coefficient values are used. Integer operations are simplerto implement than floating point operations.

The above description is only an outline of the technical schemes of thepresent invention. Preferred embodiments of the present invention areprovided below in conjunction with the attached drawings to enable onewith ordinary skill in the art to better understand said and otherobjectives, features and advantages of the present invention and to makethe present invention accordingly.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more fully understood by reading thefollowing detailed description of the preferred embodiments, withreference made to the accompanying drawings, wherein:

FIGS. 1A, 1B and 1C are schematic diagrams illustrating mutualcapacitive detection;

FIG. 2 is a schematic diagram illustrating measured signals influencedby higher-order harmonics;

FIG. 3 is a schematic diagram illustrating measuring of a sinusoidalwave at several predetermined phases of each half cycle to producemeasured signals;

FIG. 4 is a schematic diagram illustrating measured signals aftersuppressing the influences of the higher-order harmonics;

FIG. 5 is a flowchart illustrating a method for measuring signals inaccordance with a first embodiment of the present invention;

FIG. 6 is a circuit diagram illustrating a method for measuring signalsin accordance with a second embodiment of the present invention;

FIG. 7 is a circuit diagram illustrating a method for measuring signalsin accordance with a third embodiment of the present invention; and

FIG. 8 is a circuit diagram illustrating a method for measuring signalsin accordance with a fourth embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Some embodiments of the present invention are described in detailsbelow. However, in addition to the descriptions given below, the presentinvention can be applicable to other embodiments, and the scope of thepresent invention is not limited by such, rather by the scope of theclaims. Moreover, for better understanding and clarity of thedescription, some components in the drawings may not necessary be drawnto scale, in which some may be exaggerated relative to others, andirrelevant parts are omitted.

Referring to FIG. 1A, a position detecting device 100 applicable to thepresent invention is shown, which includes a sensing device 120 and adriving/detecting unit 130. The sensing device 120 has a sensing layer.In an example of the present invention, the sensing layer can include afirst sensing layer 120A and a second sensing layer 120B. The first andsecond sensing layers 120A and 120B each has a plurality of conductivestrips 140, wherein the first conductive strips 140A of the firstsensing layer 120A and the second conductive strips 140B of the secondsensing layer 120B cross each other. In another example of the presentinvention, the first and second conductive strips 140A and 140B aredisposed on a co-planar sensing layer. The driving/detecting unit 130produces sensing information based on signals of the conductive strips140. In the case of self-capacitive detection, for example, conductivestrips 140 that are being driven are detected. In the case ofmutual-capacitive detection, some of the conductive strips 140 that arenot being directly driven by the driving/detecting unit 130 aredetected. In addition, the sensing device 120 can be disposed on adisplay 110. An optional rear shielding layer (not shown) can beinterposed between the sensing device 120 and the display 110. In apreferred example of the present invention, there is no rear shieldinglayer between the sensing device 120 and the display 110 so as to reducethe thickness of the sensing device 120.

The first and second conductive strips can be a plurality of columnconductive strips and row conductive strips arranged in columns androws; a plurality of first dimensional conductive strips and seconddimensional conductive strips arranged in first and second dimensions;or a plurality of first axial conductive strips and second axialconductive strips arranged in first and second axes. In addition, thefirst and second conductive strips can be arranged in orthogonal ornon-orthogonal directions. For example, in a polar coordinate system,one of the first and second conductive strips can be arranged in radialdirection, and the other one of the first and second conductive stripscan be arranged in circular direction. Furthermore, one of the first andsecond conductive strips can be driving conductive strips, while theother one of the first and second conductive strips can be detectingconductive strips. Said “first dimension” and “second dimension”, “firstaxis” and “second axis”, “driving” and “detecting”, “driven” or“detected” conductive strips can be used to mean said “first and“second” conductive strips, including but not limited to, being arrangedin orthogonal grids, and in any other geometric configurationscomprising first dimensional and second dimensional intersectingconductive strips.

The position detecting device 100 of the present invention can beapplied to a computing system as shown in FIG. 1B, which includes acontroller 160 and a host 170. The controller includes thedriving/detecting unit 130 to operatively couple the sensing device 120(not shown). In addition, the controller 160 can include a processor 161for controlling the driving/detecting unit 130 in generating the sensinginformation. The sensing information can be stored in a memory 162 andaccessible by the processor 161. Moreover, the host 170 constitutes themain body of the computing system, and mainly includes a centralprocessing unit 171, a storage unit 173 that can be accessed by thecentral processing unit 171, and the display 110 for displaying resultsof operations.

In another example of the present invention, there is a transmissioninterface between the controller 160 and the host 170. The controllingunit transmits data to the host via the transmission interface. One withordinary skill in the art can appreciate that the transmission interfacemay include, but not limited to, UART, USB, I2C, Bluetooth, Wi-Fi, IRand other wireless or wired transmission interfaces. In an example ofthe present invention, data transmitted can be positions (e.g.coordinates), identified results (e.g. gesture codes), commands, sensinginformation or other information provided by the controller 160.

In an example of the present invention, the sensing information can beinitial sensing information generated under the control of the processor161, and this information is passed onto the host 170 for positionanalysis, such as position analysis, gesture determination, commandidentification, and so on. In another example of the present invention,the sensing information can be analyzed by processor 161 first beforeforwarding the determined positions, gestures, commands, or the like tothe host 170. The present invention does not limit to this example, andone with ordinary skill in the art can readily recognize otherinteractions between the controller 160 and the host 170.

At each intersection of the conductive strips, the upper and lowerconductive strips form the positive and negative electrodes. Eachintersection can be regarded as one pixel in an image. When one or moreexternal conductive objects approach or touch the sensing device, saidimage can be regarded as a photographed touch image (e.g. the pattern ofa finger upon touching the sensing device).

When a driven conductive strip is being provided with a driving signal,the driven conductive strip itself produces self capacitance, andproduces mutual capacitance on each intersection of the drivenconductive strip. Said self-capacitive detection is detecting theself-capacitance of all the conductive strips, which is particularlyuseful in determining approach or touch of a single external conductiveobject.

In said mutual-capacitive detection, when a driven conductive strip isbeing provided with a driving signal, capacitances or changes incapacitances of all intersections on the driven conductive strip aredetected with all sensed conductive strips arranged in differentdimensions to the driven conductive strip, and are regarded as a row ofpixels. Accordingly, all the rows of pixels are combined to form saidimage. When one or more external conductive objects approach or touchthe sensing device, said image can be regarded as a photographed touchimage, which is particularly useful in determining approaches or touchesof a plurality of external conductive objects.

These conductive strips (the first and second conductive strips) can bemade of transparent or opaque materials, such as transparent Indium TinOxide (ITO). In terms of the structure, it can be categorized into aSingle ITO (SITO) structure and a Double ITO (DITO) structure. One withordinary skill in the art can appreciate that other materials can beused as the conductive strips, such as carbon nanotube, and they willnot be further described.

In an example of the present invention, the horizontal direction isregarded as the first direction, while the vertical direction isregarded as the second direction. Thus, the horizontal conductive stripsare the first conductive strips, and the vertical conductive strips arethe second conductive strips. However, one with ordinary skill in theart can appreciate that the above is merely an example of the presentinvention, and the present invention is not limited to this. Forexample, the vertical direction can be regarded as the first direction,while the horizontal direction can be regarded as the second direction.

During 2D mutual capacitive detection, alternating driving signals aresequentially provided to each first conductive strip, and 1D sensinginformation corresponding to each driven first conductive strip isobtained from the signals of the second conductive strips. Sensinginformation of all the first conductive strips are combined together toform 2D sensing information. 1D sensing information can be generatedbased on the signal of a second conductive strip, or based on thedifference between the signal of a conductive strip and a referencevalue. In addition, the sensing information can be generated based oncurrent, voltage, level of capacitive coupling, amount of charge orother electrical characteristics, and can be in analog or digital form.

When there is no external object actually approaching or covering thetouch screen, or when the system has not determined any external objectactually approaching or covering the touch screen, the positiondetecting device may generated a reference value based on the signals ofthe second conductive strips. This reference value represents straycapacitance on the touch screen. Sensing information can be generatedbased on the signal of a second conductive strip or the result ofsubtracting the reference value from the signal of the second conductivestrip.

Referring to FIG. 1C, a schematic diagram illustrating theaforementioned 2D mutual capacitive detection is shown. A firstconductive strip T_(x) sends out a pulse width modulation (PWM) signal.Through capacitive coupling between the first conductive strip T_(x) andthe second conductive strip R_(x), a signal having the same frequencyand a certain phase difference with the signal from T_(x) is received bythe second conductive strip R.

The present invention proposes a method and device for measuring signalswhich employs signal orthogonality as the basis for signal processing.

For example, the signal received at Rx is S(t)=A sin(ωt), wherein A isthe amplitude.

∫₀ ^(T) sin(mωt)sin(nωt)dt= _(A,m=n) ^(0,m≠n), only when m=n, there areintegral values.

However, signal multiplication circuit is usually difficult to implementin practice, so traditional methods have employed square waves forimplementation, thus it becomes:

I=∫(PWM)sgn(PWM)dt.

The Fourier series of the square wave itself can be spread out andrepresented as follows:

${= {\sum\limits_{n = 0}^{\infty}\; {{\sin \left( {n\; \omega \; t} \right)} \cdot C_{n}}}},$

which is comprised of many odd harmonics. Thus, it can be rewritten as:

I=∫ ₀ ^(T) S(t)[sin(ωt)+1/3 sin(3ωt)+ . . . ]dt,

wherein S(t)=square wave or sine wave+n(t), wherein n(t) is the noise orinterference.

→I=∫[sin(ωt)+n(t)][sin(ωt)+1/3 sin(3ωt)+ . . . ]dt,

wherein the existence of odd harmonics components can be observed.

Thus, when a narrowband interference occurs in the vicinity of an oddharmonics, the effect of this interference cannot be eliminated, asshown in FIG. 2. Especially when an analog-to-digital converter (ADC) isused to sample data of the same phase at each half cycle, then add themtogether and calculate Σ (positive half cycle−negative half cycle), theinfluence of higher-order odd harmonics is more prominent.

Thus, in a best mode of the present invention, sinusoidal drive isemployed, and a coefficient table is established for a plurality ofpredetermined phases, wherein each predetermined phase is designatedwith a corresponding coefficient. In a preferred example of the presentinvention, the coefficient is a multiple of the sine value of thecorresponding predetermined phase, as shown by the table below.

TABLE 1 Phase Coefficient  30° 1  90° 2 150° 1 210° −1 270° −2 330° −1

Moreover, the sinusoidal wave is measured at the plurality ofpredetermined phases in each half cycle to generate measured signals, asshown in FIG. 3, wherein the wave is measured for at least a half cycle.Then, each measured signal is multiplied with the coefficientcorresponding to the phase at which the signal is measured to produce aweighted measured signal. The weighted signals are summed to produce acomplete measured signal.

The present invention may also employ PWM signals. Although in Table 1and FIG. 3, six measured signals are taken in one full cycle, and eachmeasurement differs a phase of 60 degrees, these are only given for thepurpose of illustration, and the present invention is not limited assuch. One with ordinary skill in the art can appreciate that two, fouror more measured signals can be taken in each full cycle, and the phasedifferences between the measured signals may not the same or different;the present invention is not limited as such.

According to the above, a complete measured signal can be

$I = {\sum\limits_{k = 0}^{nT}\; {{{AD}(k)} \cdot {{C(k)}.}}}$

Referring to the previous equation ∫₀ ^(T) sin(mωt)sin(nωt)dt=_(A, m=n)^(0, m≠n), AD(k) corresponds to sin(mωt), and C(k) corresponds tosin(nωt), wherein m=n.

In Table 1, the coefficient is double the sine value of thecorresponding phase. This is because after doubling, the results areintegers. Integer operations are simpler than floating point operations.Accordingly, in an example of the present invention, C(k) is made to bean integer, that is, multiplied by a ratio so that it becomes aninteger. As a result, the interference of higher-order harmonics can besuppressed as shown in FIG. 4.

The summing of each weighted measured signals can be implemented bydigital logic circuits. For example, after measuring an analog signal(e.g. AD(k)), the analog measured signal is converted into a digitalmeasured signal, and then summing of each weighted measured signal iscarried out. In other words, this method requires no complex circuits,but rather simple digital logic circuits.

According to the above, a method for measuring signals is provided in afirst embodiment of the present invention, as shown in FIG. 5. First, instep 510, a sinusoidal wave is received. The sinusoidal wave can beprovided by the aforementioned controller at one or a set of drivingconductive strips of a touch sensor. In addition, the sinusoidal wave isreceived by one of a plurality of sensing conductive strips in the touchsensor intersecting with the one or the set of driving conductive stripsprovided with the sinusoidal wave. The one of the plurality of sensingconductive strips receives the sinusoidal wave through capacitivecoupling with the one or the set of driving conductive strips providedwith the sinusoidal wave. Then, in step 520, signals are measured fromthe sinusoidal wave at a plurality of predetermined phases of at least acycle of the sinusoidal wave, wherein the measured signals can be in ananalog or a digital form. Next, in step 530, a weighted measured signalof the at least one cycle is produced based on a product generated bymultiplying each measured signal of the at least one cycle with the sinevalue of the predetermined phase at which the particular signal wasmeasured, wherein the weighted measured signal can be in an analog or adigital form. Thereafter, in step 540, all the weighted measured signalsof the at least one cycle are summed to produce a complete measuredsignal, wherein the complete measured signal can be in an analog or adigital form.

In an example of the present invention, each measured signal isconverted from an analog measured signal to a digital measured signal,wherein the signals measured from the sinusoidal wave are in the analogform, and each weighted measured signal is a digital product of adigital measured signal multiplied by a digital sine value. Similarly,the summing of all the weighted measured signals of the at least onecycle to produce a complete measured signal is performed in a digitalmanner. Moreover, the weighted measured signals are digital products ofdigital measured signals multiplied by respective integers, wherein eachinteger is obtained by multiplying the sine value with the samemultiple.

In another example of the present invention, each weighted measuredsignal is converted from an analog weighted measured signal to aweighted digital measured signal, wherein the measured signals are inthe analog form, and each weighted measured signal is obtained byamplifying the analog measured signal with a multiple of the sine valueof the predetermined phase at which the signal was measured. Inaddition, the summing of the weighted measured signals can be performedin an analog or a digital manner. For example, the summing of all theweighted measured signals of the at least one cycle is carried out byintegration, for example, by an integrator circuit, and wherein themeasured signals and the weighted measured signals are in analog forms.As another example, all of the weighted measured signals are firstconverted from an analog form to a digital form to produce analogweighted measured signals before summing them.

In an example of the present invention, the predetermined phases arecontinuously arranged. Adjacent phases have the same phase difference,such as 60 degrees.

FIG. 6 is a schematic diagram depicting a device for measuring signalsproposed by a second embodiment of the present invention. The deviceincludes: an analog measuring circuit 61, an analog-to-digital circuit(ADC), and a processor (e.g. a CPU). The analog measuring circuit 61receives and measures a sinusoidal wave at a plurality of predeterminedphases of at least one cycle of the sinusoidal wave to produce analogmeasured signals. In an example of the present invention, the sinusoidalwave can be represented by current, and the analog measuring circuit 61can be a current-to-voltage circuit, wherein the current I of thesinusoidal wave is converted into analog measured signals Vanalog basedon a reference resistor R. Moreover, the ADC converts each analogmeasured signal Vanalog into a digital measured signal Vdigital. Inaddition, the processor generates a digital weighted measured signal ofthe at least one cycle based on a product generated by multiplying eachdigital measured signal Vdigital of the at least one cycle with the sinevalue of the predetermined phase at which the particular signal wasmeasured, and then sums all the digital weighted measured signals of theat least one cycle to produce a complete measured signal. In an exampleof the present invention, the digital weighted measured signals aredigital products of digital measured signals Vdigital multiplied byrespective integers, wherein each integer is obtained by multiplying therespective sine value with the same multiple.

FIG. 7 is a schematic diagram depicting a device for measuring signalsproposed by a third embodiment of the present invention. The deviceincludes: an analog measuring circuit 71, an amplifying circuit 72, anADC, and a processor (e.g. a CPU). The analog measuring circuit 71receives and measures a sinusoidal wave at a plurality of predeterminedphases of at least one cycle of the sinusoidal wave to produce analogmeasured signals Vanalog. The amplifying circuit 72 then amplifies eachanalog measured signal Vanalog by a multiple of the sine value of thepredetermined phase at which the particular signal was measured toproduce an analog weighted measured signal VWanalog. In an example ofthe present invention, a set of variable resistors 73 can be used todetermine the multiple. The ADC then converts each analog weightedmeasured signal VWanalog into a digital weighted measured signalVWdigital. Next, the processor sums all of the digital weighted measuredsignals VWdigital of the at least one cycle to produce a completemeasured signal.

FIG. 8 is a schematic diagram depicting a device for measuring signalsproposed by a fourth embodiment of the present invention. The deviceincludes: an analog measuring circuit 81, an amplifying circuit 82, anintegrator circuit 84, and an ADC. The analog measuring circuit 81receives and measures a sinusoidal wave at a plurality of predeterminedphases of at least one cycle of the sinusoidal wave to produce analogmeasured signals Vanalog. The amplifying circuit 82 then amplifies eachanalog measured signal Vanalog by a multiple of the sine value of thepredetermined phase at which the particular signal was measured toproduce an analog weighted measured signal VWanalog. In an example ofthe present invention, a set of variable resistors 83 can be used todetermine the multiple. The integrator circuit 84 performs integrationon all of the analog weighted measured signals VWanalog of the at leastone cycle to produce an analog complete measured signal VOanalog.Thereafter, the ADC converts each analog complete measured signalVOanalog into a digital complete measured signal VOdigital.

The above analog measuring circuit can be implemented by an integratorcircuit or a sample-and-hold circuit, or any other circuit that iscapable of receiving a sinusoidal wave; the present invention is notlimited as such.

The above embodiments are only used to illustrate the principles of thepresent invention, and they should not be construed as to limit thepresent invention in any way. The above embodiments can be modified bythose with ordinary skill in the art without departing from the scope ofthe present invention as defined in the following appended claims.

What is claimed is:
 1. A method for measuring signals comprising:receiving a sinusoidal wave; measuring signals from the sinusoidal waveat a plurality of predetermined phases of at least a cycle of thesinusoidal wave; producing a weighted measured signal of the at leastone cycle based on a product generated by multiplying each measuredsignal of the at least one cycle with the sine value of thepredetermined phase at which the particular signal was measured; andsumming all of the weighted measured signals of the at least one cycleto produce a complete measured signal.
 2. The method of claim 1, furthercomprising: providing the sinusoidal wave at one or a set of drivingconductive strips of a touch sensor; and receiving the sinusoidal waveby one of a plurality of sensing conductive strips in the touch sensorintersecting with the one or the set of driving conductive stripsprovided with the sinusoidal wave, the one of the plurality of sensingconductive strips receiving the sinusoidal wave through capacitivecoupling with the one or the set of driving conductive strips providedwith the sinusoidal wave.
 3. The method of claim 1, further comprising:converting each measured signal from an analog measured signal to adigital measured signal, wherein the signals measured from thesinusoidal wave are in an analog form, and each weighted measured signalis a digital product of a digital measured signal multiplied by adigital sine value.
 4. The method of claim 1, wherein the weightedmeasured signals are digital products of digital measured signalsmultiplied by respective integers, wherein the integers are obtained bymultiplying the respective sine value with the same multiple.
 5. Themethod of claim 1, further comprising: converting each weighted measuredsignal from an analog weighted measured signal to a digital weightedmeasured signal, wherein the measured signals are in an analog form, andeach analog weighted measured signal is obtained by amplifying theanalog measured signal with a multiple of the sine value of thepredetermined phase at which the signal was measured.
 6. The method ofclaim 1, wherein the summing of all the weighted measured signals of theat least one cycle is carried out by integration, and the measuredsignals and the weighted measured signals are in the analog form.
 7. Themethod of claim 1, wherein the predetermined phases are continuouslyarranged, and wherein adjacent phases have the same phase difference. 8.The method of claim 1, wherein the phase difference is 60 degrees.
 9. Adevice for measuring signals comprising: an analog measuring circuit forreceiving a sinusoidal wave and measuring analog signals from thesinusoidal wave at a plurality of predetermined phases of at least acycle of the sinusoidal wave; an analog-to-digital converter forconverting each analog measured signal into a digital measured signal;and a processor for producing a digital weighted measured signal of theat least one cycle based on a product generated by multiplying eachdigital measured signal of the at least one cycle with the sine value ofthe predetermined phase at which the particular signal was measured, andsumming all of the digital weighted measured signals of the at least onecycle to produce a complete measured signal.
 10. The device of claim 9,wherein the digital weighted measured signals are digital products ofthe digital measured signals multiplied by respective integers, whereinthe integers are obtained by multiplying the respective sine value withthe same multiple.
 11. The device of claim 9, wherein the predeterminedphases are continuously arranged, and wherein adjacent phases have thesame phase difference.
 12. The device of claim 11, wherein the phasedifference is 60 degrees.
 13. A device for measuring signals comprising:an analog measuring circuit for receiving a sinusoidal wave andmeasuring analog signals from the sinusoidal wave at a plurality ofpredetermined phases of at least a cycle of the sinusoidal wave; anamplifying circuit for amplifying each analog measured signal with amultiple of the sine value of the predetermined phase at which theparticular signal was measured to produce an analog weighted measuredsignal; an analog-to-digital converter for converting each analogweighted measured signal into a digital weighted measured signal; and aprocessor for summing all of the digital weighted measured signals ofthe at least one cycle to produce a complete measured signal.
 14. Thedevice of claim 13, wherein the predetermined phases are continuouslyarranged, and wherein adjacent phases have the same phase difference.15. The device of claim 14, wherein the phase difference is 60 degrees.16. A device for measuring signals comprising: an analog measuringcircuit for receiving a sinusoidal wave and measuring analog signalsfrom the sinusoidal wave at a plurality of predetermined phases of atleast a cycle of the sinusoidal wave; an amplifying circuit foramplifying each analog measured signal with a multiple of the sine valueof the predetermined phase at which the particular signal was measuredto produce an analog weighted measured signal; an integrator circuit forperforming integration on all of the analog measured signals of the atleast one cycle to produce an analog complete measured signal; and ananalog-to-digital converter for converting each analog complete measuredsignal into a digital complete measured signal.
 17. The device of claim16, wherein the predetermined phases are continuously arranged, andwherein adjacent phases have the same phase difference.
 18. The deviceof claim 17, wherein the phase difference is 60 degrees.